1. Field
The present disclosure relates to a throttle control device in which a motor is driven being based on an operational amount of a throttle grip and the like by a driver and an air-intake amount to an engine is controlled by controlling opening of a throttle valve with the motor.
2. Description of the Related Art
In the related art, there has been known a throttle control device in which an operational amount of a throttle grip and the like is detected by an accelerator sensor and throttle valve opening is controlled by driving a motor based on the operational amount as shown in, for example, Japanese Patent Publication No. 2002-256895, which discloses that a throttle valve placed at an outer side is operated by a motor commonly with a throttle valve adjacent thereto even in a case that four throttle valves are operated by two motors.
As illustrated in FIG. 3, when a throttle valve in the related art is mounted on an engine of a motorcycle, temperature of the vicinity of throttle valves 104, 105 placed at the inner side of a throttle body becomes relatively high compared to that of the vicinities of throttle valves 102, 103 placed at the bilateral outer sides of the throttle body as being cooled by external air.
Further, in a case that four exhaust pipes 106, 107, 108, 109 for respective cylinders are aggregated into a single pipe, two exhaust pipes 107, 108 placed at the inner side are shorter than two exhaust pipes 106, 109 placed at the outer sides owing to limitation of internal space of the motorcycle. Accordingly, there may be a case that air-intake inertia effect of cylinders at the inner side is different from that of cylinders at the outer sides. Here, when the throttle valves 102, 103 corresponding to the outer side cylinders and the throttle valves 104, 105 corresponding to the inner cylinders are controlled commonly by a single motor 110, there may be a fear of variation occurrence among air-fuel ratios of the respective cylinders.